1. Field of the Invention
The invention relates to an gas measurement module that is insertable into a ventilation circuit, and carries a microspectrometer configured to detect gas composition within the ventilation circuit.
2. Description of the Related Art
Gas analyzers are widely used in medical applications and may be characterized as being located either in the main path of the patient's respiratory gases (mainstream analyzers) or in an ancillary path usually paralleling the main path (sidestream analyzers). A mainstream analyzer is situated such that the subject's inspired and expired respiratory gases pass through an airway adapter onto which the analyzer is placed. A sidestream gas analyzer is coupled to an airway adapter to draw air off from the main respiratory circuit for measurement. Mainstream and sidestream designs for inclusion in gas measurement modules that can be coupled to a respiratory circuit in a therapeutic setting to measure gas composition must be designed to facilitate installation of the gas measurement modules at a patient's airway or in a respiratory circuit in communication with a patient in a location in relatively close proximity to the patient. As a result, to be accepted in therapeutic settings, the gas analyzer must be designed such that the gas measurement module housing the gas analyzer has a convenient and comfortable form factor and/or weight. Further, the gas analyzer must be robust enough to be substantially unaffected by typical mechanical abuse and temperature variations associated with use in therapeutic settings.
While gas measurement modules with gas analyzers employing scanning spectrometers are known, the optics typically employed in these systems to process electromagnetic radiation generally form an optical path having a shape that adversely impacts the overall form factor of the spectrometer, and the gas measurement module as a whole. This impact may be due to one or both of the bulk of the optics and/or the optical path length and orientations dictated to process the electromagnetic radiation appropriately. Further, attempting to reduce the size of the optics and/or enhance the optical path lengths and orientations required to by conventional optics may result in the design of optical configurations that are not robust enough to withstand therapeutic settings and/or optical components that are prohibitively expensive.